Analysis and future trends of cyclodextrins as adsorbents in wastewater treatment

Abstract

Cyclodextrins, derived from starch, are introduced as promising adsorbents capable of sequestering various pollutants, including heavy metals and dyes, although their solubility in water poses challenges for their removal after use. In this paper a bibliometric analysis is conducted using the Scopus database, yielding 649 relevant documents. Analysis indicates that the use of cyclodextrins in wastewater treatment is still in the early stages of growth and maturity, with most studies focusing on their application as adsorbents for dyes and heavy metals. However, the influence of other wastewater constituents on their effectiveness remains underexplored. By means of an S-growth model, it can be stated that this technology requires at least another 10 years to reach maturity as a treatment process. The geographic performance analysis indicates that China is the leading contributor to research on cyclodextrins in wastewater treatment, accounting for 40% of total publications, followed by the United States. Finally, the performance and operating conditions of cyclodextrins as adsorbents have been analysed. It is discussed the variations in adsorption capacity and the challenges in comparing studies due to differing initial contaminant concentrations. The results suggest that in the future it will be necessary to carry out experiments with real wastewater in pilot-scale plants.